Answer:
The dimensions are 68 meters by 42 meters.
Explanation:
Let the length be x
Let the width be y
Perimeter = 220 meter
So,

or
or
...........(1)
Area = 2856 square meter
So,
............(2)
Substituting the value of x from (1) in (2)

=>

=>

Solving this equation, we get roots as y = 68 and y = 42
So, if we put y = 68, we get x = 42
If we put y = 42, we get x = 68
As length is longer than width, we will take length = 68 meters and width = 42 meters.
Hence, the dimensions are 68 meters by 42 meters.